1 80 N O V UM ORG A N U M . 



Here, too, we must not rest contented with a vague re 

 sult, but inquire into the exact proportion of quantity 

 requisite for a particular exertion of power. For one would 

 be apt to suppose that the power bears an exact proportion 

 to the quantity ; that if a leaden bullet of one ounce, for in 

 stance, would fall in a given time, one of two ounces ought 

 to fall twice as rapidly, which is most erroneous. Nor does 

 the same ratio prevail in every kind of power, their difference 

 being considerable. The measure, therefore, must be &quot;de 

 termined by experiment and not by probability or con 

 jecture. 



Lastly, we must in all our investigations of nature observe 

 what quantity, or dose, of the body is requisite for a given 

 effect, and must at the same time be guarded against 

 estimating it at too much or too little. 



48. In the twenty-fourth rank of prerogative instances 

 we will place Wrestling instances, which we are also wont to 

 call instances of predominance. They are such as point out 

 the predominance and submission of powers compared with 

 each other, and which of them is the more energetic and 

 superior, or more weak and inferior. For the motions and 

 effects of bodies are compounded, decomposed, and com 

 bined, no less than the bodies themselves. We will exhibit, 

 therefore, the principal kinds of motions or active powers, 

 in order that their comparative strength, and thence a de 

 monstration and definition of the instances in question, may 

 be rendered more clear. 



Let the first motion be that of the resistance of matter, 

 which exists in every particle, and completely prevents its 

 annihilation; so that no conflagration, weight, pressure, 

 violence, or length of 1 time, can reduce even the smallest 

 portion of matter to nothing, or prevent it from being 

 something, and occupying some space, and delivering itself 

 (whatever straights it be put to), by changing its form or 

 place, or, if that be impossible, remaining as it is, nor can 

 it ever happen that it should either be nothing or nowhere. 

 This motion is designated by the schools (which generally 

 name and define every thing by its effects and inconve 

 niences rather than by its inherent cause) by the axiom; 

 &quot; that two bodies cannot exist in the same place,&quot; or they 

 call it a motion &quot; to prevent the penetration of dimensions.&quot; 

 It is useless to give examples of this motion since it exists 

 in every body. 



Let the second motion be that which we term the motion 

 of connexion, by which bodies do not allow themselves to 

 be separated at any point from the contact of another body, 



